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Abundance d = sigma(N) - 2*N = A033880(N) of numbers N = A153501(n), i.e., N has d > 0 as divisor.
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%I #28 Sep 13 2019 21:16:55

%S 4,3,2,12,10,8,4,2,120,7,56,78,8,2,2,672,32,16,4,2,532,152,136,8,68,

%T 31,992,128,8,64,32,16,4,8,128,32,8,2,43648,2528,32,4,2,523776,32,

%U 2272,32,32,127,16256,32,32,4,536,8,32,8,52,16,32,41044,64

%N Abundance d = sigma(N) - 2*N = A033880(N) of numbers N = A153501(n), i.e., N has d > 0 as divisor.

%C It is conjectured that only powers of 2 can occur more than once.

%C Thanks to _Amiram Eldar_, reference to A181595 in the definition has been corrected to A153501 (which does include triperfect numbers, as required here, in contrast to A181595 where these are excluded). - _M. F. Hasler_, Sep 11 2019

%H M. F. Hasler, <a href="/A182142/b182142.txt">Table of n, a(n) for n = 1..200</a>, Sep 11 2019

%F Equals A033880 o A153501.

%o (PARI) f182142(n)={my(d=sigma(n)-2*n); d>0 && !(n%d) && return(d)} /* Note: This is A033880(n)*is_A153501(n), neither A182142 nor is_A182142. */

%o for(n=1,1e6,(t=f182142(n))&&print1(t","))

%Y Cf. A033880, A153501, A181595.

%K nonn

%O 1,1

%A _M. F. Hasler_, Apr 14 2012